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1.
Opt Express ; 19(3): 2676-93, 2011 Jan 31.
Article in English | MEDLINE | ID: mdl-21369089

ABSTRACT

This paper aims to establish and develop a calibration model for two time-of-flight terrestrial laser scanners (TLS): Trimble GX200 and Riegl LMS-Z390i. In particular, the study focuses on measurement errors and systematic instrumental errors to compile an error model for TLS. An iterative and robust least squares procedure is developed to compute internal calibration parameters together with a TLS data set geo-reference in an external reference system. To this end, a calibration field is designed that performs as an experimental platform that tests the different laser scanner methods. The experimental results show the usefulness and potential of this approach, especially when high-precision measurements are requires.


Subject(s)
Algorithms , Image Enhancement/methods , Lasers , Calibration
2.
Neurology ; 66(9): 1367-72, 2006 May 09.
Article in English | MEDLINE | ID: mdl-16682669

ABSTRACT

OBJECTIVE: To examine the contribution of neuropsychological test performance to treatment decision-making capacity in community volunteers with mild to moderate dementia. METHODS: The authors recruited volunteers (44 men, 44 women) with mild to moderate dementia from the community. Subjects completed a battery of 11 neuropsychological tests that assessed auditory and visual attention, logical memory, language, and executive function. To measure decision making capacity, the authors administered the Capacity to Consent to Treatment Interview, the Hopemont Capacity Assessment Interview, and the MacCarthur Competence Assessment Tool--Treatment. Each of these instruments individually scores four decisional abilities serving capacity: understanding, appreciation, reasoning, and expression of choice. The authors used principal components analysis to generate component scores for each ability across instruments, and to extract principal components for neuropsychological performance. RESULTS: Multiple linear regression analyses demonstrated that neuropsychological performance significantly predicted all four abilities. Specifically, it predicted 77.8% of the common variance for understanding, 39.4% for reasoning, 24.6% for appreciation, and 10.2% for expression of choice. Except for reasoning and appreciation, neuropsychological predictor (beta) profiles were unique for each ability. CONCLUSIONS: Neuropsychological performance substantially and differentially predicted capacity for treatment decisions in individuals with mild to moderate dementia. Relationships between elemental cognitive function and decisional capacity may differ in individuals whose decisional capacity is impaired by other disorders, such as mental illness.


Subject(s)
Cognition , Decision Making , Dementia/psychology , Informed Consent , Mental Competency , Neuropsychological Tests , Aged , Aged, 80 and over , Attention , Choice Behavior , Comprehension , Educational Status , Female , Humans , Language Tests , Male , Memory , Predictive Value of Tests , Verbal Learning
3.
Microb Ecol ; 44(2): 127-36, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12087423

ABSTRACT

The cyanobacteria belonging to the genus Nostoc fix atmospheric nitrogen, both as free-living organisms and in symbiotic associations with a wide range of hosts, including bryophytes, gymnosperms (cycads), the small water fern Azolla (Pteridophyte), the angiosperm genus Gunnera, and fungi (lichens). The Gunnera-Nostoc symbiosis is the only one that involves a flowering plant. In Chile, 12 species of Gunnera have been described with a broad distribution in the temperate region. We examined the genetic diversity of Nostoc symbionts from three populations of Gunnera tinctoria from Abtao, Chiloé Island, southern Chile, and microsymbionts from other two species of Gunnera from southern Chile, using PCR amplification of STRR (short tandemly repeated repetitive) sequences of the Nostoc infected tissue. To our knowledge, this is the first report of PCR fingerprinting obtained directly from symbiotic tissue of Gunnera. Genetic analyses revealed that Nostoc symbionts exhibit important genetic diversity among host plants, both within and between Gunnera populations. It was also found that only one Nostoc strain, or closely related strains, established symbiosis with an individual plant host.


Subject(s)
Cyanobacteria/genetics , DNA Fingerprinting , Genetic Variation , Plants , Symbiosis/physiology , Tandem Repeat Sequences/genetics , Cyanobacteria/physiology , DNA, Bacterial/analysis , DNA, Bacterial/genetics , Polymerase Chain Reaction
4.
Fam Process ; 40(2): 145-61, 2001.
Article in English | MEDLINE | ID: mdl-11444053

ABSTRACT

This study examined factors that contribute to parental rejection of gay and lesbian youth. College students (N = 356) were asked to imagine being the parent of an adolescent son who recently disclosed that he was gay. Consistent with study hypotheses and based on attribution and moral affect theory, results of regression analyses indicated that greater perceptions of control over homosexuality, higher proneness to experience shame, and lower proneness to experience guilt were associated with increasing negative reactions toward an imagined homosexual child. Also in line with study hypotheses, greater willingness to offer help to the hypothetical child was predicted by lower perceptions of control over homosexuality, less intensely unfavorable emotional reactions, less proneness to experience guilt, and greater reported likelihood of experiencing affection toward him. Theoretical and clinical implications of this research are discussed.


Subject(s)
Guilt , Homosexuality/psychology , Parenting/psychology , Adolescent , Adult , Analysis of Variance , Female , Humans , Love , Male , Middle Aged , Shame , Surveys and Questionnaires
5.
Science ; 287(5459): 1770-4, 2000 Mar 10.
Article in English | MEDLINE | ID: mdl-10710299

ABSTRACT

Scenarios of changes in biodiversity for the year 2100 can now be developed based on scenarios of changes in atmospheric carbon dioxide, climate, vegetation, and land use and the known sensitivity of biodiversity to these changes. This study identified a ranking of the importance of drivers of change, a ranking of the biomes with respect to expected changes, and the major sources of uncertainties. For terrestrial ecosystems, land-use change probably will have the largest effect, followed by climate change, nitrogen deposition, biotic exchange, and elevated carbon dioxide concentration. For freshwater ecosystems, biotic exchange is much more important. Mediterranean climate and grassland ecosystems likely will experience the greatest proportional change in biodiversity because of the substantial influence of all drivers of biodiversity change. Northern temperate ecosystems are estimated to experience the least biodiversity change because major land-use change has already occurred. Plausible changes in biodiversity in other biomes depend on interactions among the causes of biodiversity change. These interactions represent one of the largest uncertainties in projections of future biodiversity change.


Subject(s)
Ecosystem , Agriculture , Animals , Atmosphere , Carbon Dioxide , Climate , Fresh Water , Models, Biological , Nitrogen
6.
Mol Ecol ; 8(6): 975-87, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10434418

ABSTRACT

Fitzroya cupressoides (alerce, Cupressaceae) is a large and exceptionally long-lived conifer, endemic to a restricted area of southern Chile and neighbouring areas of Argentina. As a result of its high economic value, the species has been severely exploited for timber, and remnant populations are fragmented and often highly disturbed. The species is thought to have undergone a major range contraction during the last glaciation. In order to assess the extent of genetic variation using DNA markers within and between populations of this species, samples were obtained from throughout the natural range and analysed for random amplified polymorphic DNA (RAPD) variation. Eight 10-mer and three 15-mer primers were used to produce a total of 54 polymorphic bands. Shannon's diversity estimates were calculated to provide an estimate of the degree of variation within each population. Values varied from 0.343 to 0.636 with only the lowest value differing significantly from the others (Spop = 0.547). This indicated that there is a significant degree of variation within each population, and did not provide evidence for genetic 'bottle-neck' effects within the species. A pairwise distance measure calculated from the RAPD data was used as an input for principal coordinate (PCO) and AMOVA analyses. The first three principal coordinates of RAPD distances described 8.3, 5.9 and 5.4% of the total variance, respectively, and a degree of clustering of samples according to their geographical origin was detectable. AMOVA analysis indicated that although most of the variation (85.6%) was found within populations, a significant proportion (P < 0.002) was attributable to differences between populations. An UPGMA dendrogram constructed using phi ST values derived from AMOVA produced a pattern broadly similar to that produced by the PCO, highlighting differences between three main groups of populations within Chile: those from the northern Coastal Range, the southern Coastal Range and Central Depression, and the Andes. Populations from Argentina also emerged as significantly different from those in Chile. These results are interpreted in the context of the postglacial history of the species, and their implications for the development of conservation strategies for Fitzroya are discussed.


Subject(s)
Conservation of Natural Resources , Genetic Variation , Trees/genetics , DNA, Plant/chemistry , DNA, Plant/genetics , Random Amplified Polymorphic DNA Technique , South America
7.
Pharmacol Res ; 39(1): 55-9, 1999 Jan.
Article in English | MEDLINE | ID: mdl-10366332

ABSTRACT

The anti-inflammatory effect of c-phycocyanin extract was studied in acetic acid-induced colitis in rats. Phycocyanin (150, 200 and 300 mg kg(-1) p.o.) was administered 30 min gbefore induction of colitis with enema of 1 ml of 4% acetic acid per rat. Twenty-four hours later myeloperoxidase (MPO) activity was determined as well as histopathological and ultrastructural studies were carried out in colonic tissue. Phycocyanin substantially reduced MPO activity which was increase din the control colitis group. Also, histopathological and ultrastructural studies were carried out in colonic tissue. Phycocyanin substantially reduced MPO activity which was increased in the control colitis group. Also, histopathological and ultrastructural studies showed inhibition in inflammatory cell infiltration and reduction to some extent in colonic damage in rats treated with phycocyanin. The probable role of antioxidative and the scavenging properties of phycocyanin against reactive oxygen species in the anti-colitic effect is discussed in this paper. To our knowledge this is the first report on the anti-inflammatory effect of phycocyanin in an experimental model of colitis.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Colitis/prevention & control , Peroxidase/metabolism , Phycocyanin/pharmacology , Acetic Acid , Animals , Colitis/chemically induced , Eukaryota/chemistry , Male , Mesalamine/pharmacology , Microscopy, Electron , Peroxidase/drug effects , Rats , Rats, Sprague-Dawley
8.
Pharmacol Res ; 39(1): 1055-1059, 1999 Jan.
Article in English | MEDLINE | ID: mdl-10079148

ABSTRACT

The anti-inflammatory effect of c-phycocyanin extract was studied in acetic acid-induced colitis in rats. Phycocyanin (150, 200 and 300 mg kg-1 p.o.) was administered 30 min before induction of colitis with enema of 1 ml of 4% acetic acid per rat. Twenty-four hours later myeloperoxidase (MPO) activity was determined as well as histopathological and ultrastructural studies were carried out in colonic tissue. Phycocyanin substantially reduced MPO activity which was increased in the control colitis group. Also, histopathological and ultrastructural studies showed inhibition in inflammatory cell infiltration and reduction to some extent in colonic damage in rats treated with phycocyanin. The probable role of antioxidative and the scavenging properties of phycocyanin against reactive oxygen species in the anti-colitic effect is discussed in this paper. To our knowledge this is the first report on the anti-inflammatory effect of phycocyanin in an experimental model of colitis.(c) 1999 The Italian Pharmacological Society.

9.
Inflamm Res ; 47(1): 36-41, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9495584

ABSTRACT

OBJECTIVE: Phycocyanin is a pigment found in blue-green algae which contains open chain tetrapyrroles with possible scavenging properties. We have studied its antioxidant properties. MATERIALS AND METHODS: Phycocyanin was evaluated as a putative antioxidant in vitro by using: a) luminol-enhanced chemiluminescence (LCL) generated by three different radical species (O2-, OH., RO.) and by zymosan activated human polymorphonuclear leukocytes (PMNLs), b) deoxyribose assay and c) inhibition of liver microsomal lipid peroxidation induced by Fe+2-ascorbic acid. The antioxidant activity was also assayed in vivo in glucose oxidase (GO)-induced inflammation in mouse paw. RESULTS: The results indicated that phycocyanin is able to scavenge OH. (IC50 = 0.91 mg/mL) and RO. (IC50 = 76 microg/mL) radicals, with activity equivalent to 0.125 mg/mL of dimethyl sulphoxide (DMSO) and 0.038 microg/mL of trolox, specific scavengers of those radicals respectively. In the deoxyribose assay the second-order rate constant was 3.56 x 10(11) M(-1) S(-1), similar to that obtained for some non-steroidal anti-inflammatory drugs. Phycocyanin also inhibits liver microsomal lipid peroxidation (IC50 = 12 mg/mL), the CL response of PMNLs (p < 0.05) as well as the edema index in GO-induced inflammation in mouse paw (p < 0.05). CONCLUSIONS: To our knowledge this is the first report of the antioxidant and anti-inflammatory properties of c-phycocyanin.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal , Antioxidants , Cyanobacteria/chemistry , Phycocyanin/therapeutic use , Animals , Deoxyribose/metabolism , Free Radical Scavengers , Free Radicals , Glucose Oxidase , Humans , Hydroxyl Radical/metabolism , Inflammation/chemically induced , Inflammation/drug therapy , Lipid Peroxidation/drug effects , Luminescent Measurements , Male , Mice , Microsomes, Liver/metabolism , Neutrophils/metabolism , Rats , Rats, Sprague-Dawley , Zymosan/pharmacology
10.
Eur J Biochem ; 238(1): 259-69, 1996 May 15.
Article in English | MEDLINE | ID: mdl-8665945

ABSTRACT

Digestion of calf intestine alkaline phosphatase with pronase and subsequent dephosphorylation of the released peptidyl-(Etn-P)2-glycosyl-PtdIns with HF generated 8 glycosyl-Ins species the largest of which (G1 and G2) have the following proposed structures: [sequence: see text] G3 and G5 are lower homologues of G1 and G2, respectively, being one alpha 1-2 linked mannopyranosyl residue shorter. G4 is analogous to G2 lacking the N-acetylgalactosaminyl residue and G6 is the next lower homologue of G4. Most of G4 and G6 occur substituted with a palmitoyl (G4, G6) or a myristoyl residue (G6) probably attached to the inositol moiety. Thus, the basic ManxGlc-Ins species are either substituted with an N-acetylgalactosaminyl residue or a fatty acid ester. The structures were deduced from compositional analysis, molecular-mass determination by matrix-assisted laser desorption MS, sequential hydrolysis with appropriate exoglycosidases and treatment with CrO3. Purification of the glycosylinositol species was achieved by a novel reverse-phase HPLC technique using fluorescent fluoren-9-yl-methoxy-carbonyl (Fmoc) derivatives. These stable derivatives were susceptible to hydrolysis with exoglycosidases which allowed sequential cleavages to be carried out and kinetics to be followed at the picomole level. We observed recently that native alkaline phosphatase separates on octyl-Sepharose into four distinct fractions of increasing hydrophobicity (F1-F4). Here we show that all four fractions contain G1-G6. The acylated species G4 and G6 were restricted to F2 and F4 which had been shown earlier to contain, on average, 2.5 and 3 fatty acid residues/subunit, respectively. In all four fractions the diradylglycerol moiety was predominantly diacylglycerol, alkylacylglycerol being less than 10% which is in contrast to most glycosyl-PtdIns--anchored proteins of mammalian origin.


Subject(s)
Alkaline Phosphatase/chemistry , Glycoproteins/chemistry , Glycosylphosphatidylinositols/chemistry , Intestines/enzymology , Acetylgalactosamine/chemistry , Alkaline Phosphatase/metabolism , Animals , Carbohydrate Sequence , Cattle , Chemical Fractionation , Diglycerides/chemistry , Fatty Acids/analysis , Fluorenes , Glycoside Hydrolases/metabolism , Glycosylphosphatidylinositols/metabolism , Hydrolysis , Inositol , Intestines/chemistry , Mannose/chemistry , Molecular Sequence Data , Structure-Activity Relationship
11.
Eur J Biochem ; 217(1): 199-207, 1993 Oct 01.
Article in English | MEDLINE | ID: mdl-8223555

ABSTRACT

A method is described for large-scale purification of glycosylphosphatidylinositol-anchored alkaline phosphatase from intestinal mucosa and chyme to homogeneity. Both enzyme preparations contain approximately 2 mol fatty acid/mol subunit and exhibit a very similar fatty acid composition with octadecanoate and hexadecanoate as prevalent components. No significant differences between native glycosylPtdIns-anchored and hydrophilic alkaline phosphatases from both sources were found regarding Km, Vmax, the type of inhibition and inhibition constants of the amino acids L-leucine, L-phenylalanine, and L-tryptophan. The purified enzymes of both sources yield diacylglycerol and phosphatidic acid, after treatment with phosphatidylinositol-specific phospholipase C (PtdIns-PLC) and glycosylphosphatidylinositol phospholipase D (PLD), respectively. Enzyme preparations of both sources appear as heterogeneous mixtures of five fractions separable by octyl-Sepharose chromatography. Fraction I corresponds to the anchorless enzyme, fractions II-V differ in their susceptibility to phospholipases. Fractions II and IV are completely split by PtdIns-PLC or PLD action, almost 50% of fraction III is split by PtdIns-PLC, while fraction V is resistant. The susceptibility of these two fractions toward the action of PLD is considerably higher. Fatty acid analysis yields molar ratios of fatty acids/alkaline phosphatase subunit of 1.78, 2.58, 2.24, and 3.37 for fractions II, III, IV, and V, respectively. Aggregates of glycosylPtdIns-anchored alkaline phosphatase of all fractions are seen in native PAGE in the presence of Triton X-100. By gel chromatography in the presence of Brij 35, fractions II-V form stable multiple aggregates of dimers and may bind different amounts of the detergent. These data, together with fatty acid analysis, can be interpreted by the following model. Fractions II and IV are tetramers and octamers with two molecules fatty acid/subunit. Fraction III is a tetramer, bearing one additional fatty acid molecule, localized on the dimer. Fraction V is an octamer, containing glycosylPtdIns-anchor molecules with three molecules fatty acids/anchor molecule. The additional fatty acid residue is possibly located on inositol and responsible for the reduced susceptibility to PtdIns-PLC. The similarity of all measured parameters of both enzymes suggests that the glycosylPtdIns-anchored alkaline phosphatase of the mucosa is released into the chyme without changing the anchor molecule constituents.


Subject(s)
Alkaline Phosphatase/metabolism , Glycosylphosphatidylinositols/metabolism , Intestinal Mucosa/enzymology , Animals , Cattle , Electrophoresis, Polyacrylamide Gel , Fatty Acids/analysis , Glycosylphosphatidylinositols/analysis , Glycosylphosphatidylinositols/antagonists & inhibitors , Kinetics , Leucine/pharmacology , Molecular Weight , Phenylalanine/pharmacology , Phospholipase D/metabolism , Tryptophan/pharmacology , Type C Phospholipases/metabolism
12.
Agents Actions ; 39(1-2): 69-71, 1993 May.
Article in English | MEDLINE | ID: mdl-8285143

ABSTRACT

Glutathione reductase activity from mice liver is significantly enhanced by lobenzarit disodium at concentrations between 0.3 and 1.5 mM. A maximum activation of almost 30% is achieved at a drug concentration of 0.9 mM. Similar results were observed with glutathione reductase from human leukocytes, but not with the enzyme from yeast. By preincubation with the enzyme from mice liver, lobenzarit also proved to prevent, at least partially, the immediate inhibition caused by the well-known thiol-reacting agents, thus indicating a protecting effect on the catalytically important thiol residue of the enzyme. The results here obtained explain in part the recently found hepatoprotective effect of lobenzarit disodium against acute liver toxicity induced by acetaminophen in mice.


Subject(s)
Glutathione Reductase/metabolism , Immunosuppressive Agents/pharmacology , Liver/enzymology , ortho-Aminobenzoates/pharmacology , Animals , Enzyme Activation/drug effects , Humans , Hydrogen-Ion Concentration , In Vitro Techniques , Leukocytes/drug effects , Leukocytes/enzymology , Liver/drug effects , Mice
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